Fuel pumping apparatus



E. A. ROCKWELL. 2,080,392

FUEL PUMPING APPARATUS Filed June 8. 1935 Jamaal Z Z Z6 I:I 16

I 43 i? 44 19 3 g 41 I 18' 1 1? I I I 5 INVENTOR I EdWardARw/zn elPatented May 11, 1937 UNITED STATES PATENT I OFFICE j V 2,080,392 FUELPUMPING APPARATUS Application June 8, 1935, Serial No. 25,573 2 Claims.(Cl. 103-154) My invention relates particularly to a fuel pumpingapparatus designed for use in connection with internal combustionengines and which is applicable to automotive vehicles of all'kinds.

The object of my invention is to provide a fuel pumping means havingmany advantages over previous fuel pumping devices. The object isparticularly-to provide an apparatus which may be readily constructedand with a minimum of cost and labor and which will more effectivelyperform the pumping of the fuel to the internal combustion engine, as,for instance, an internal combustion engine provided with any desiredtype of carbureter. A further object is to provide a pumping mechanismof the type involving a diaphragm as a pumping element, having a pistonassociated therewith in an advantageous manner. Another object is toprovide an eflicient guide for the diaphragm, or piston, or both, in

0 which guide the outlet valve can be mounted in order to reduce theclearances and make a more compact construction possible. A furtherobject is to locate the guide in a cushioning dome on the outlet side ofthe pump. Again, a further object is to mount the operating springs forthe pumping element in such a manner as to make the construction morecompact and better adapted for large scale production. Still a furtherobject is to provide the inlet with an auxiliary passageway to the pumpsuch as to supplement the action of the pumping stroke spring and at thesame time return to the inlet passageway any excess of fuel which mightseep by the piston. Another objectis to provide a secondary chamber inconnection with the inlet passageway, so arranged as to facilitate theflow of the incoming fuel while permitting the above mentioned action ofthe fluid through said auxiliary passageway. Further objects of myinvention will appear from the detailed description hereinafter.

While my invention is capable of being carried out in many differentways, for the purpose of illustration I have shown certain embodimentsof my invention in the accompanying drawing, in which- Fig. l is avertical section of a fuel pumping 0 apparatus made in accordance withmy invention;

Fig. 2 is a plan view of the same; Fig; 3 is a side elevation showingthe lever mechanism for operating the pump;

Fig. 4 is an elevational detail of the means for connecting the saidlever to the diaphragm;

and

Fig. 5 is a vertical detailed section showing a modified form of filter.i

In the drawing I have shown an upwardly bent lever I having an outer end2 adapted to ride on an operating cam of any desired character, drivenby an internal combustion engine, as, for example, the engine driving anautomobile. This lever I has a recess 3 in the elbow of the bent portionthereof to receive a transverse pivot l which passes through the twosides of a U-shaped bracket 5 secured to the lever I on opposite sidesthereof by rivets 6, said pivot 4' being journaled in a lower pumpcasing I having a flange 8 for attachment to the side of the casing ofsaid engine. Said bracket 5, furthermore, has an upwardly and backwardlyturned tongue 9 to co-act with the end of a horizontal spring l0 whichis carried ina cylindrical spring-pocket ll formed. in the lower pumpcasing l. The spring I0 is provided for keeping the end of the lever 2in contact with the cam. The other end l2 of said lever is carried in aU-shaped strap or stirrup '13 provided at its lower portion with aleather bu'fier M which is held in place at one side by an ear l5 and atthe other side by a transversely bent member l6 on the stirrup 13 whichalso serves to protect the end l2 of the lever from contacting with thelower pump casing I. The two upper ends of the strap l3 are connected bya pin l1 and a cotterpin l8 to a stem I9 having a nut 20 for holding inplace a laminated diaphragm 2|, the periphery of which is clampedbetween the lower pump casing I and an upper pump casing 22. Between thesaid nut 20 and the diaphragm 2| there is also a flanged lowersupporting disk 23 for the diaphragm 2|. Also above said diaphragm 2|there is an upper convex supporting disk 24. Above the disk 24 there isfurthermore carried by the stem IS a piston disk 21 which supports atits periphery a plurality of self-centering bakelite piston rings 26looselyconfined in place by a recessed clamping disk 25 in such a mannerthat the piston rings 26 loosely fit within a piston chamber 28 in theupper pump casing 22. The

' recessed clamping disk 25 fits against a shoulder 29 on the stem l9,forming a hollow guide member 30 having a transverse inlet passageway 3|and a vertical outlet passageway 32 communicating with a chamber 33 inthe guide member in which there is seated an outlet check valve 34against an upturned lip 35 and which is held in place by a spring 36supported by a strap 31 with downwardly bent lateral portions to act asa stop for the valve 34 so as to be sprung into recesses 38 in thechamber 33. Said guide 30 is arranged to reciprocate in the lowerportion of an air cushioning dome 39 formed in the upper pump casing 22.An outlet 40 conveys the pumped fuel to a carbureter of any desiredcharacter of the internal combustion engine. Around the stem l3 there isfurthermore provided a pumping-stroke spring 4| in a recess 42 in thelower pump casing 1 and adjacent to the recess 42 there is an annularchamber 43 connected to the outer air by a vent 44. At one side of theguide member 30 there is situated an inlet port member 45 forming a seatfor an inlet check valve 46 which is held in place by a spring 41supported by a strap 48 similar in construction to the strap 31. Theinlet port member 45 communicates with a horizontal inlet passageway 49which leadsto an auxiliary inlet passageway 50 forming a by-pass aroundthe inlet valve 46 so as to not only return fuel which leaks past thepiston rings 26 back to the passageway 49, but also serves to supplementthe action of the pumping spring 4| in the pumping stroke due to thedecreased pressure that has been produced in the inlet passageway 49.The inlet passageway 49 leads to a vertical passageway 5| throughwhichthe fuel enters due to a plug 52 which closes this end of thepassageway 49. Said vertical passageway 5| projects downwardly into aremovable dirt trap or gascolator 53 in such a manner as to form aninlet suction space 54. The ga'scolator 53 is preferably of glass, andis held in place by a pivoted yoke member 55 having a flared button 56,bearing on the lower face of the gascolator 53 and adapted to be pressedagainst the same by a thumb-screw 51. 'I'hegascolator 53 is thus clampedto the upper pump casing 52 by the yoke 55 against a gasket 58 and aperforated filter-supporting member 59, having a gauze filter 60, whichfits against the lower end of the vertical passageway 5|. Above thestrainer 59 there is a vertical inlet 6| leading to a horizontal inlet62 which is connected in any desired manner to the low-level gasolinesupply tank on the automobile.

The modification of the invention shown in Fig. 5 is constructed thesame as the form of the invention already described except that in thisinstance there is an annular gauze filter I53 fitting around the lowerend of an inlet passageway 64 connected to a horizontal inlet 65 thesame as the inlet 62. In this instance a plug 66 closes ofi thepassageway 65 at the right of the vertical passageway 64, thus leavingan outlet passageway 61 communicating with a vertical passageway 68above the gauze filter 63.

In the operation of my invention, referring first to Figs. l'to 4, theend of the pump-operating lever 2 will be moved to the left, in Fig 1,by the engine cam to retract the diaphragm piston pump. This results indrawing into the pump chamber 28 fuel from the lower gasoline supplytank through the passageways 62 and 6|,

perforated filter-support 59 and thence into the gascolator 53, afterwhich the fuel will pass through the filter 80 and the passageways 5|,49 and 45 to the inlet valve 46 and thence into the pump chamber 28.There will thus be a decreased pressure produced in the passageway 49and. the auxiliary passageway 50 causing the return of any fuel whichseeps past the piston rings 26 back to the passageway 49 and this actionwill at the same time supplement the force of the pump-spring 4| on thepump stroke which now-takes place due to said spring 4|, the end 2 ofthe lever being returned to its initial position by the follower springIll. The fuel will thus be discharged through the outlet valve 34 intothe vapor pressure dome 39 and thence by the outlet 40 to the enginecarbureter.

It will be noted that in the pumping operations of the diaphragm 2| andthe piston the rings 26, which are loosely carried in the cylinder 28between the clamping plate 21 and the piston 25, will accommodatethemselves to the interior of the cylinder 28 without interfering withthe guiding of the piston within said cylinder, the guiding beingaccomplished by the hollow guide member 80. This operation'isfacilitatedby the fact that the stirrup I3 is capable of pivotal lateralmovement with regard to the stem l9 during the actuation of the stem l9by the lever While I have described my invention above in detail I wishit to be understood that many changes may be made therein withoutdeparting from the spirit of the same.

I claim:

1. A fuel pump having relatively movable parts forming a pump chamber, afirst tubular member carried by and movable with one of said relativelymovable members, a second tubular member surrounding and guiding saidfirst tubu-- larmember and having unrestricted communication with thedischarge opening from said pump, said pump having an outlet valvelocated in said first tubular member.

2. A pump comprising a housing formed with a pump chamber, a pistonreciprocable in said chamber, a tubular member secured to andreciprocable with said piston, a tubular guide therefor, said guidefreely communicating with the discharge opening from said pump, means toreciprocate said piston, 'a diaphragm centrally clamped to said pistonand peripherally secured to said housing, inlet and outlet valvescommunicating with said chamber, said outlet valve being within saidreciprocable tubular member, said housing having an inlet passageleading to the inlet valve, a compensating passage extending at rightangles to said inlet passage'and leading from said inlet passage to aspace ad-. jacent the periphery of said diaphragm whereby leakage aroundthe piston is restored to the inlet passage and the force of the pistonreciprocating means is augmented,

EDWARD A. ROCKWELL.

